Asynchronous IO (UNIX)

Steve_Dodsworth_at_qsp.co.uk wrote:

>Hello All,
 

>After reading numerous books and having countless arguments, I assume the following to be true.
 

>If the unix operating system supports asynchronous IO then set an init.ora flag called use_async_io to true ONLY if the datafiles etc are to be stored on raw devices.
 

>If the datafiles are stored on 'normal' file systems then set this flag to false (default) and instead set at least as many db_writers as there are disks used to store the datafiles on.
 

>An exception to this is AIX, which can use kernal settings to achieve asynchronous IO. In this case set use_async_io to true and db_writers to 1.

>If anyone knows any different or indeed knows any more exceptions - can they please reply
>Thanks
 

>Steve Dodsworth
 

> T.C.
> ___________________________________________________________
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> disclaimer-in-a-box

FYI, I faced some trouble when using asynchronous I/O with ORACLE 7.0.16 for SCO UNIX some months ago. The ORACLE instance trapped an operating system ERROR and entered the shutdown procedures. The database didn't get corrupted, but smooth operation was impossible. Maybe it's a problem specific to this release and/ or my UNIX configuration.

Coming back to your main point, as far as I know you're totally right.

Best regards Received on Fri Sep 29 1995 - 00:00:00 CET